1. Field of the Invention
The present invention relates to disk chucks which center and clamp data storage disks and, more particularly, to a disk chuck designed to clamp or unclamp a plurality of disks at the same time.
2. Description of the Prior Art
In general, data storage disks such as magnetic disks for hard disk drives (HDD) of computers store data and programs thereon for a later retrieval. However, it is impossible to store data or programs on such disks unless they are formatted after they are manufactured. During a disk formatting process, tracks are densely formed on a disk and are sectored, thus allowing the disk to effectively store the data and programs.
In an effort to quickly perform such a disk formatting process and to improve the efficiency of performing the process, the disk formatting process is typically performed at a pre-assembly operation prior to assembling the hard disk drives (HDD) on an HDD production line. In addition, a disk chuck which centers and clamps disks is designed and used to center and clamp the disks at the same time, so as to simultaneously format the disks during a formatting process.
FIG.1 shows a conventional disk chuck used in a disk formatting process disclosed by a Japanese Patent Laid-open Publication No. 2000-11569. The conventional disk chuck comprises a mandrel 3 coupled to a receiver plate 2 of a spindle motor 1. A pin 5 is axially fitted in a central bore of the mandrel 3 so as to extend upward to a predetermined height in a vertical direction. A plurality of disks 4 are fitted over the pin 5 to be stacked in the vertical direction. A plurality of spacers 6 are fitted over the pin 5 at corresponding positions between the disks 4 and space the disks 4 from each other by a predetermined parallel gap. The disk chuck also has a disk clamp 8, which is screwed to a top end of the pin 5 using a setscrew 7 which clamps the disks 4.
In order to clamp the disks 4 using the disk chuck, the disks 4 and the spacers 6 are alternately fitted over the pin 5 of the mandrel 3 to the top end of the pin 5 prior to clamping the disks 4 by screwing the clamp 8 to the top end of the pin 5. After clamping the disks 4, the spindle motor 1 is turned on to rotate the disks 4, thus performing a disk formatting process. After the completion of the disk formatting process, the clamp 8 is removed from the top end of the pin 5 by loosening the setscrew 7, thus unclamping both the disks 4 and the spacers 6. The disks 4 and the spacers 6 are, thereafter, removed from the pin 5. After removing the formatted disks 4, new disks are clamped on the disk chuck so as to be subjected to the same formatting process.
However, with a conventional disk chuck, an operator must manually mount and remove the clamp 8 to and from the top end of the pin 5 by tightening and loosening the setscrew 7. This labor-intensive process is repeated for each disk formatting process and makes the conventional disk chuck inconvenient to use.
In addition, a circumferential surface of the pin 5 is abraded due to a repeated disk clamping operation. Therefore, the pin 5 may fail to precisely center the disks 4, causing an error during a disk formatting process.